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#[inline]
#[deprecated]
pub fn clamp<N>(a: N, min: N, max: N) -> N
where
N: PartialOrd,
{
if a < min {
return min;
}
if a > max {
return max;
}
a
}
pub(crate) fn resize_dimensions(width: u32, height: u32, nwidth: u32, nheight: u32, fill: bool) -> (u32, u32) {
let ratio = u64::from(width) * u64::from(nheight);
let nratio = u64::from(nwidth) * u64::from(height);
let use_width = if fill {
nratio > ratio
} else {
nratio <= ratio
};
let intermediate = if use_width {
u64::from(height) * u64::from(nwidth) / u64::from(width)
} else {
u64::from(width) * u64::from(nheight) / u64::from(height)
};
let intermediate = std::cmp::max(1, intermediate);
if use_width {
if intermediate <= u64::from(::std::u32::MAX) {
(nwidth, intermediate as u32)
} else {
(
(u64::from(nwidth) * u64::from(::std::u32::MAX) / intermediate) as u32,
::std::u32::MAX,
)
}
} else if intermediate <= u64::from(::std::u32::MAX) {
(intermediate as u32, nheight)
} else {
(
::std::u32::MAX,
(u64::from(nheight) * u64::from(::std::u32::MAX) / intermediate) as u32,
)
}
}
#[cfg(test)]
mod test {
quickcheck! {
fn resize_bounds_correctly_width(old_w: u32, new_w: u32) -> bool {
if old_w == 0 || new_w == 0 { return true; }
let result = super::resize_dimensions(old_w, 400, new_w, ::std::u32::MAX, false);
result.0 == new_w && result.1 == (400 as f64 * new_w as f64 / old_w as f64) as u32
}
}
quickcheck! {
fn resize_bounds_correctly_height(old_h: u32, new_h: u32) -> bool {
if old_h == 0 || new_h == 0 { return true; }
let result = super::resize_dimensions(400, old_h, ::std::u32::MAX, new_h, false);
result.1 == new_h && result.0 == (400 as f64 * new_h as f64 / old_h as f64) as u32
}
}
#[test]
fn resize_handles_fill() {
let result = super::resize_dimensions(100, 200, 200, 500, true);
assert!(result.0 == 250);
assert!(result.1 == 500);
let result = super::resize_dimensions(200, 100, 500, 200, true);
assert!(result.0 == 500);
assert!(result.1 == 250);
}
#[test]
fn resize_never_rounds_to_zero() {
let result = super::resize_dimensions(1, 150, 128, 128, false);
assert!(result.0 > 0);
assert!(result.1 > 0);
}
#[test]
fn resize_handles_overflow() {
let result = super::resize_dimensions(100, ::std::u32::MAX, 200, ::std::u32::MAX, true);
assert!(result.0 == 100);
assert!(result.1 == ::std::u32::MAX);
let result = super::resize_dimensions(::std::u32::MAX, 100, ::std::u32::MAX, 200, true);
assert!(result.0 == ::std::u32::MAX);
assert!(result.1 == 100);
}
}